Non-Celiac Wheat Sensitivity

Hypothesizing an intestinal barrier impairment as a common pathophysiological substrate of both Non Celiac Wheat Sensitivity (NCWS) and Metabolic Dysfunction-Associated Steatotic Liver Disease (MAFLD), in a retrospective cohort study (data not yet published), demographic, clinical, laboratory and histology data of NCWS patients at the time of diagnosis, were analyzed and compared to control subjects with Irritable Bowel Syndrome/Functional Dyspepsia (IBS/FD) and freshly diagnosed Celiac Disease (CeD). NCWS diagnosis was performed by a double-blind placebo-controlled wheat challenge. Steatosis was confirmed by ultrasound examination. Our retrospective data showed that the frequency of liver of steatosis was lower in NCWS than in IBS patients. In addition, it seems that pre-diagnosis avoidance of wheat in NCWS correlates with protection from steatosis. A subset of NCWS patients, recently exposed to wheat, with clinical features suggesting increased IP, seems to be predisposed to liver steatosis and fibrosis. To validate the results of the retrospective study, the researchers planned the present prospective study, to analyze the prevalence of liver steatosis and fibrosis, evaluated by ultrasound (US) examination, FibroScan analysis \[CAP (Controlled Attenuation Parameter) and LSM (Liver Stiffness Measurement) values\], FIB-4 (Fibrosis-4) index, and NFS \[Non-alcoholic fatty liver disease (NAFLD) Fibrosis Score\], in patients with NCWS at the time of diagnosis, comparing them with two control populations of newly diagnosed IBS/FD and CeD patients.

Over 50% of non-celiac wheat sensitivity (NCWS) patients are HLA DQ2/DQ8 positive and often have a Celiac Disease (CD) family history. Studies have identified a subgroup of NCWS patients whose clinical and immunological features are closer to CD than to irritable bowel syndrome/functional dyspepsia (IBS/FD) ('inflammatory subgroup'). The investigators hypothesized that among CD patient's relatives, there might be a high number of NCWS subjects, who hypothetically belong to the 'inflammatory subgroup'. Therefore, the aim of this multi-step project is to identify the prevalence of both self-reported NCWS and IBS/FD not related to wheat ingestion among CD patient's relatives (parents, grandparents, siblings and sons).

Non-celiac gluten sensitivity (NCGS) is a condition where intestinal and extraintestinal symptoms are triggered by gluten ingestion in the absence of celiac disease and wheat allergy. Despite the great interest in NCGS, much remains unknown about the pathogenesis. Some studies seem to suggest that wheat components other than gluten (i.e. amylase/trypsine inhibitors, ATIs) can cause the symptoms, and therefore the term "non-celiac wheat sensitivity" (NCWS) has been proposed instead of NCGS. It is believed that this condition is worldwide increasing, due to the evolution of wheat breeding (i.e. consumption of wheats with high gluten content), and that ancient wheats are better tolerated by NCWS patients than the modern ones. Therefore, the aim of the study is to determine whether the common belief regarding the fact that ancient wheats are better tolerated by NCWS patients than the modern ones is confirmed by scientific data, and to identify the wheat kernel components triggering this pathology. The availability of wheat materials with opposite characteristics, such as the period of development (ancient vs. modern), or the technological properties (cultivars with weak glutens vs. strong gluten), or the presence/absence of specific ATIs polypeptides, will allow to define the role played by these factors. Therefore, the study has two objectives: 1) extraction and testing of total kernel proteins, in order to evaluate the inflammatory response to gluten and non-gluten proteins by peripheral blood mononuclear cells (PBMC) and immunocytes extracted by the rectal mucosa of NCWS patients and healthy control subjects, and 2) clinically testing two wheat genotypes, selected on the basis of the previous in vitro studies, showing the highest and the lowest in vitro inflammatory response, in order to verify their effect in triggering NCWS symptoms.